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(No Model.) 2 Sheets-Sheet 1.

T. EDWARDS. FURNACE FOR ROASTING OR ES.

N0. 53%024. Patented Apr.9,'1895.

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(No Model.) 2 Sheets-Sheet 2.

7 T. EDWARDS. FURNACE FOR ROASTING'ORES.

Patented Apr. 9, 1895.

In ZIBZZZOK fz m 6%- UNITED STATES,

PATENT ()FFIGEE.

THOMAS EDWARDS, or SEBASTOPOL'VIOTORIA.

FURNACE FOR ROASTING ORES.

SPECIFICATION forming part of Letters Patent No. 537,024, dated AprilQ, 18 95.

Application filed August 22,13941 Serial No. 520,988. (No model.)

To all whom it may concern:

Be it known that I, THOMAS EDWARDS, metallurgist, a subject of the Queen of Great Britain and Ireland, and a resident of Sebastopol, Ballarat, in the Colony of Victoria, Australia, have invented certain new and'useful Improvements in Furnaces for the Roasting of Ores and for other Purposes, of which the following is a specification.

My invention relates to roasting-furnaces whereby pyrites, matte, tin-ore, quartz and other sulphurous-ores and other compounds may be efficiently and economically roasted and if desired chloridized.

The invention consists of improvements in and relating to reverberatory furnaces in which coarse or finely divided ores are roasted, and in illustration of the same drawings are attached, in which- Figure 1 shows a sketch in side elevation of a reverberatory furnace containing my improvements. Fig. 2 shows a side elevation as in Fig. l partly invertical middle section. Fig. 3 shows a plan view of the same furnace, partly in longitudinal section to show the interior of the furnace. Fig. 4 is an end elevation showing frame and driving gear. Fig. 5 is a transverse vertical section of the furnace on the line or win Figs. 1 to 3 showing doors on each side, also discharge hole, and

opening in arch for rabbles, with stays, tie- Figs. 6 to 9 show (on a bolts and trunnions. larger scale than in Figs. 2 and 3) details of rabbles which may be used in the said furnaces.

The furnace is portable and maybe made of any suitable dimensions or material. The drawings represent the invention as applied to a furnace, A, constructed of iron exteriorly, and lined with brick arch or roof, B, sides, 0,

' and bottom or hearth. The whole construcsonic, still consists in the use of the long reverberatory furnace having a plane hearth. One well-known and serious drawback to the latter is, however, the large expense of work ing, owing to the methods of rabbling heretofore used with that form of furnace. Hand rabbling is also very irregularly done, on account of the trying nature of the work; and as a result, the ore is not roasted uniformly or properly. Mechanical rabbles have been devised in various forms, such as endless drag chains; or a number of rabbles have been connected to a central spindle and worked me- 6 chanically, in conjunction with superposed hearths, in using which, dust is raised and carried out of the flues and large losses consequently occur. These losses also occur in some cases'with revolving or cylindrical fur- 7o naces, which have also been devised to work without any rabbles and in some of which the action of gravity alone carries the ore along. These have no flat hearth D on which the crushed metalliferous material maybe spread out in a thin uniform layer. The first novel feature I adopt is the making of a reverberatory furnace pivoted so as to swing or be adjustable longitudinally (and not in any other direction).

The furnace is fitted with any suitable number of rabbles, E, and F, which are specially arranged in relation to one another. To facilitate the tilting of the furnace there I are providedtrunnions G resting on supports H and so placed that the furnace shall balance easily and be easily placed in a horizon tal position and as easily be moved or tilted so as to adjust the hearth to any desired inclination longitudinally while the rabbles are in motion andore roasting is proceeding.

Jacks or other contrivances not shown in drawings may be used to move the furnace.

Z is a short flue or box affixed to the end of the furnace, and which may project into any 5 suitable fixed flue (not shown) for leading away the smoke and other gaseous products of combustion to the chimney.

Any suitable driving gear may be used, so

arranged that the adjustment or tilting up 1:0

and down of the furnace does not interfere with the working of the rabbles. Thus a pulley as J may be driven by belting from ashaft placed in'a line with the trunnions, and by means of intermediate gearing drive a longitudinal shaft as K. Fine crushed highly concentrated pyrites cannot be properly roasted on a hearth, the incline of which is suited to a more coarse ground and badly concentrated ore, and the method aforesaid is that I adopt to meet this difliculty, while retaining the long reverberatory furnace, which I adapt at the same time to be rabbled by mechanical means. The slope should be adjusted to assist the moving of the ore along the hearth, or to prevent it traveling too rapidly, as the case may require. The ore may thus be kept in the furnace for a sufficienttime to be thoroughly oxidized, and on the completion thereof, be discharged by one or more apertures as L. Fresh ore may be introduced frequently, or regularly, at any suitable openings in the roof and the furnace be kept continuously working to its full capacity. The upper rabble opening next described may be utilized for this purpose.

I prefer to make openings at intervals as at M along the length of the furnace in the crown of the arch B from the feed end of the furnace P, to the discharge end, and I insert through each of them one of my rabbles, which consists of a foot, or feet, extending parallel to the hearth and slightly above same, forming a stirrer, or stirrers, and an upright, N, arranged to project through a bushing or opening in the movable plates, O,Which rest on a flange extending around or partly around the apertures, M, and by which plates said apertures are usually kept closed. These uprights N form a longitudinal series and may be worked by adjustable gearing of any suitable kind, so that at the will of the attendant, all, or some of them, may be revolved simultaneously and uniformly, or intermit' tently, any suitable motive power being utilized.

The rabbles may be of any desired kind and suitable material. These mechanical rabbles insure the necessary thorough stirring and turning over of the ore, and gradually sweep or transfer it in a regular manner from the locality of one sweep or rabble, to

. that of the next adjacent, so as to gradually convey it from the feed end of the furnace to g the discharge end.

My rabbles are so arranged that one or more may be stopped for a suitable time. The arrangement for this purpose which I prefer, is shown in the drawings in which toothed bevel wheels, Q, feathered on the shaft, K, are arranged to work in gear with toothed wheels, S, (teeth not shown in either case in drawings) on the spindles, R, thereby enabling the rabbles to be rotated, but each wheel, Q, may be adapted to be slipped along the shaft, K, out of gear with S, whereupon the corresponding spindles R will cease to be rotated.

My rabbles are so arranged that any one, or the whole of them may be raised to the crown of the furnace, or be removed altogether, in either case allowing the 'rabbling to be done by hand. This might be effected in various ways, one being to have a series of holes T in the head of the rabble whereby the same might be suitably pinned or fastened as shown in Fig. 8 within the hollow base U of the spindle. The spindles R are in such relative proximity that the stirring feet of each pair of adjacent rabbles describe circles at their outer ends (shown by dotted lines), which cut one another as shown.

In order that the ore may be transferred by one rabble into the area which is swept by the next rabble, and then pushed by the latter rabble to the area swept by a third rabble. and so on, the rabbles are rotated in opposite directions, as shown byarrows in the drawings. This I elfect by makingv each pair of wheels Q gear with the wheels S at opposite sides of the latter, as will be understood from the drawings. Thus the ore while roasting and oxidizing, and being stirred and turned over, is moved along a course which is partly circular, and partly zig-zag, from the feed hole to the discharge hole, which it reaches free from clotting and caking. The bridge, the edge of which is shown by the line 0 prevents the ore from passing too far down the furnace.

The form of rabble may be varied to meet the requirement of particular cases, as also may the speed of rotation. them at a slow speed.

The feet of the rabbles I prefer to use are of two kinds; one kind as shown in Figs. 6 and 7 and the other by Figs. 8 and 9. The plain rabble E is preferably used at the upper and lower ends of the furnace, and that fitted with the spikes IV is preferably employed in the middle part of the furnace, where the greatest part of the sulphur is volatilized. The greatest efficiency of these rabbles is obtained only when working in combination with a furnace inclined to asuitable slope to suit the ore.

It will be observed that these rabbling feet are of novel form.

The plain rabble E has no teeth, and is calculated to stir the ore gently, passing under much of it, while pushing some around as it rotates. The spiked rabble has its teeth of any suitable form, individually, and set at any desired angle but always projecting upward from the foot, and preferably at the back of the same; and this tends to break up and prevent clots forming and turns over the surface of the ore, better than with rabbles having the teeth underneath, as is usual. In both rabbles, E, and F, a stay, as g, is preferably added, and in both there are one or more holes as T for adjustment, as aforesaid.

It is not essential to employ all of my improvements at once, and various obvious modifications might be made in the arrangement of details, and in the position of parts. The arrangement of the furnace on trunnions, or so that it may be swung to any slope, may be in some cases dispensed with. A fixed incline might be adopted and the stirrers or rabbles be introduced through openings as M shown in the drawings (from which they can be easily removed when required), all motion and advantages, as far as the rabbling and its gearing are concerned, being the same as in the swing furnace shown on plan; or the furnace may be arranged so-as to be adjustable /to any angle, and the mechanical rabbles here described be replaced by other apparatus or rabbled by' hand.

I do not limit my claim to trunnions placed as on drawings, as the use of pivots or other supports in suitable position by which the furnace might be tilted conveniently would be an equivalent device.

Instead of the hearth being plane throughout it may be made with one or more shallow steps as shown by Y Fig. 2 so that when the ore is fed the first rabble shifts it on to the next step or hearth proper, which is not subject to the influence of that rabble, but is to that of the next rabble. This keeps the feed end of the hearth clear.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. In combination, the elongated tilting hearth, having a series of openings above the same, the longitudinal shaft above said hearth and tilting therewith, the vertical spindles driven from said shaft and having their lower ends in proximity to the openings, and the rabbles having their stems extending up through the openings and connected with the spindles,'substantially as described.

2. A mechanical rabble for furnaces comprising the spindle, the laterally extending arm at the lower end thereof having a beveled edge, and the projections extending upward from the upper face of said arm, substantially as described.

3. In combination with a reverberatory f urnace the plain rabbles arranged to revolve at each end thereof, and the intermediate revolving rabbles having upwardly extending projections, substantially as described.

In witness whereof I have hereunto set my hand in the presence of two subscribing witnesses.

THOMAS EDWARDS;

Witnesses:

GEORGE G. TUNI,

Patent Solicitor, Melbourne. E. F. NIoHoLLs, Clerk to the above. 

